SCTA is a crucial assessment designed to predict and understand the role that human error plays in major accidents.
[3] This is a type or workshop conducted to support Major Accident Hazard (MAH) industries, such as oil and gas, chemicals.
Those activities or tasks that are identified as being safety critical (i.e. may result in significant impact to the environment or harm to people if completed incorrectly), are put through an SCTA which would break down the task into a step-by-step process and review where the most likely points of error are to occur.
The aim of this is to identify where additional control measures can be introduced that would reduce the likelihood of human error in completing such an important task.
Tasks may be identified and defined at multiple levels of abstraction as required to support the purpose of the analysis.
A critical task analysis, for example, is an analysis of human performance requirements which, if not accomplished in accordance with system requirements, will likely have adverse effects on cost, system reliability, efficiency, effectiveness, or safety.
Cognitive task analysis is applied to modern work environments such as supervisory control where little physical work occurs, but the tasks are more related to situation assessment, decision making, and response planning and execution.
The advantages If task analysis is likened to a set of instructions on how to navigate from Point A to Point B, then Work domain analysis (WDA) is like having a map of the terrain that includes Point A and Point B. WDA is broader and focuses on the environmental constraints and opportunities for behavior, as in Gibsonian ecological psychology and ecological interface design (Vicente, 1999; Bennett & Flach, 2011, p. 61) Since the 1980s, a major change in technical documentation has been to emphasize the tasks performed with a system rather than documenting the system itself.
[9] This task orientation in technical documentation began with publishing guidelines issued by IBM in the late 1980s.
[10] With the development of XML as a markup language suitable for both print and online documentation (replacing SGML with its focus on print), IBM developed the Darwin Information Typing Architecture XML standard in 2000.
HTA is used to produce an exhaustive description of tasks in a hierarchical structure of goals, sub-goals, operations and plans.
HTA is a task description method which is most commonly used as a starting point for further analyses such as multimodal CPA and SHERPA.